Having trouble with multiple animations triggered by key presses in the game engine
The problem is that the action actuator is broken since 2.62. When you play different actions one after the other at the same object, some animations will not be shown. The bugtracker contains several reports already.

To avoid that problem you can play the animations with python via playAction().

It is not my preferred solution, but as long as the action actuator does not work as expected, it is a solution.